Title :
Phase noise measurement techniques using delta-sigma TDC
Author :
Osawa, Yusuke ; Hirabayashi, Daiki ; Harigai, Naohiro ; Kobayashi, Hideo ; Niitsu, Kiichi ; Kobayashi, Osamu
Author_Institution :
Div. of Electron. & Inf., Gunma Univ., Kiryu, Japan
Abstract :
This paper describes two techniques for measuring phase noise of a clock using a delta-sigma time-to-digital converter (TDC). One technique uses a reference signal (which has only very small phase noise), and the other does not use a reference signal. Both proposed techniques can be implemented with relatively simple circuitry, due to the following: (i) The clock under test (CUT) is a repetitive signal. (ii) The time resolution with CUT and a reference clock can be increased by using longer measurement time with the delta-sigma TDC. (iii) The phase noise power spectrum can be calculated from the delta-sigma TDC output data using FFT. Costly high-performance spectrum analyzers which average several-time phase measurement results over a long measurement time (about 10s order), are not needed for phase noise measurement with the proposed technique. The other technique, which differs in that it uses a self-referenced clock rather than a reference signal, has potential wide applications.
Keywords :
clocks; delta-sigma modulation; fast Fourier transforms; noise measurement; phase measurement; phase noise; spectral analysers; time-digital conversion; CUT; clock under test; delta-sigma time-to-digital converter; fast Fourier transform; measurement time; phase noise measurement; power spectrum; reference clock; reference signal; repetitive signal; self-referenced clock; simple circuitry; spectrum analyzers; time phase measurement; Clocks; Frequency measurement; Noise measurement; Phase measurement; Phase noise; Semiconductor device measurement; Delta-Sigma Modulation; PLL Testing; Phase Noise Measurement; Time-to-Digital Converter;
Conference_Titel :
Mixed-Signals, Sensors and Systems Test Workshop (IMS3TW), 2014 19th International
Conference_Location :
Porto Alegre
DOI :
10.1109/IMS3TW.2014.6997392